1. Field of the Invention
The invention relates to a device for movably supporting an upper mold tool with respect to a lower mold tool.
2. Description of Related Art
In two-part mold tools, it is known that the upper mold tool can be moved by means of a simple pivoting drive from a closed working position, in which the upper mold tool and the lower mold tool are closed for production of workpiece in them by injection or casting, into an open feed position and a removal or maintenance position in which the upper mold tool is held at a distance above the lower mold tool for inserting casting inserts, for removing the finished workpiece and/or for cleaning the mold.
The defect in this configuration is that the space between the mold tools, especially when the workpieces are large, is only very poorly accessible. To some extent, this defect is remedied by a second drive enabling horizontal displacement of the top mold tool in addition to the pivoting motion. However, this greatly increases the complexity, and thus, the costs of such a device.
The primary object of this invention is to devise a device in which much better accessibility is enabled with simultaneously economical production.
This object is achieved by the upper mold tool being supported on a frame by means of a multi-bar mechanism, such as a four-bar mechanism or a six-bar mechanism
The significance of the invention is that, by the upper mold tool being mounted on a frame by means of a four-bar mechanism or a multi-bar mechanism, the resulting path of movement of the upper mold tool produces a very wide opening of the space between the two mold tools.
According to one advantageous embodiment, it is provided that the upper mold tool is coupled to a vertically extending part of the frame by means of a tension rod and a triangular lever. Here, a leg of the triangular lever in conjunction with the tension rod forms a four-bar mechanism, and a drive for producing a pivoting motion is coupled to the another corner of the triangular lever.
Advantageously, the ratio of the work arm to the power arm on the triangular lever is roughly two to one. In this way, a relatively large swinging path of the upper mold tool can be achieved with a small actuating path of the drive.
Preferably, the lower mold tool is also pivotally mounted on the frame. This enables an ergonomically advantageous position for removing the workpieces and for cleaning the mold.
One embodiment of the invention is described in detail below, by way of example only, with reference to the accompanying the drawings.